V4L/DVB (9801): cx18: Allow more than 63 capture buffers in rotation per stream

[safe/jmp/linux-2.6] / drivers / media / video / cx18 / cx18-queue.c

diff --git a/drivers/media/video/cx18/cx18-queue.c b/drivers/media/video/cx18/cx18-queue.c
index fdfc83e..40379d8 100644 (file)
--- a/drivers/media/video/cx18/cx18-queue.c
+++ b/drivers/media/video/cx18/cx18-queue.c
@@ -42,24 +42,32 @@ void cx18_queue_init(struct cx18_queue *q)
        q->bytesused = 0;
 }
 
-void _cx18_enqueue(struct cx18_stream *s, struct cx18_buffer *buf,
-                  struct cx18_queue *q, int to_front)
+struct cx18_queue *_cx18_enqueue(struct cx18_stream *s, struct cx18_buffer *buf,
+                                struct cx18_queue *q, int to_front)
 {
-       /* clear the buffer if it is going to be enqueued to the free queue */
-       if (q == &s->q_free) {
+       /* clear the buffer if it is not to be enqueued to the full queue */
+       if (q != &s->q_full) {
                buf->bytesused = 0;
                buf->readpos = 0;
                buf->b_flags = 0;
                buf->skipped = 0;
        }
+
        mutex_lock(&s->qlock);
+
+       /* q_busy is restricted to 63 buffers to stay within firmware limits */
+       if (q == &s->q_busy && atomic_read(&q->buffers) >= 63)
+               q = &s->q_free;
+
        if (to_front)
                list_add(&buf->list, &q->list); /* LIFO */
        else
                list_add_tail(&buf->list, &q->list); /* FIFO */
-       atomic_inc(&q->buffers);
        q->bytesused += buf->bytesused - buf->readpos;
+       atomic_inc(&q->buffers);
+
        mutex_unlock(&s->qlock);
+       return q;
 }
 
 struct cx18_buffer *cx18_dequeue(struct cx18_stream *s, struct cx18_queue *q)
@@ -70,9 +78,9 @@ struct cx18_buffer *cx18_dequeue(struct cx18_stream *s, struct cx18_queue *q)
        if (!list_empty(&q->list)) {
                buf = list_entry(q->list.next, struct cx18_buffer, list);
                list_del_init(q->list.next);
-               atomic_dec(&q->buffers);
                q->bytesused -= buf->bytesused - buf->readpos;
                buf->skipped = 0;
+               atomic_dec(&q->buffers);
        }
        mutex_unlock(&s->qlock);
        return buf;
@@ -85,28 +93,30 @@ struct cx18_buffer *cx18_queue_get_buf(struct cx18_stream *s, u32 id,
        struct cx18_buffer *buf;
        struct cx18_buffer *ret = NULL;
        struct list_head *p, *t;
-       LIST_HEAD(r);
 
        mutex_lock(&s->qlock);
-       list_for_each_safe(p, t, &s->q_free.list) {
+       list_for_each_safe(p, t, &s->q_busy.list) {
                buf = list_entry(p, struct cx18_buffer, list);
 
                if (buf->id != id) {
                        buf->skipped++;
-                       if (buf->skipped >= atomic_read(&s->q_free.buffers)-1) {
+                       if (buf->skipped >= atomic_read(&s->q_busy.buffers)-1) {
                                /* buffer must have fallen out of rotation */
-                               atomic_dec(&s->q_free.buffers);
-                               list_move_tail(&buf->list, &r);
                                CX18_WARN("Skipped %s, buffer %d, %d "
                                          "times - it must have dropped out of "
                                          "rotation\n", s->name, buf->id,
                                          buf->skipped);
+                               /* move it to q_free */
+                               list_move_tail(&buf->list, &s->q_free.list);
+                               buf->bytesused = buf->readpos = buf->b_flags =
+                                       buf->skipped = 0;
+                               atomic_dec(&s->q_busy.buffers);
+                               atomic_inc(&s->q_free.buffers);
                        }
                        continue;
                }
 
                buf->bytesused = bytesused;
-               atomic_dec(&s->q_free.buffers);
                if (s->type == CX18_ENC_STREAM_TYPE_TS) {
                        /*
                         * TS doesn't use q_full, but for sweeping up lost
@@ -116,28 +126,19 @@ struct cx18_buffer *cx18_queue_get_buf(struct cx18_stream *s, u32 id,
                         */
                        list_del_init(&buf->list);
                } else {
-                       atomic_inc(&s->q_full.buffers);
-                       s->q_full.bytesused += buf->bytesused;
                        list_move_tail(&buf->list, &s->q_full.list);
+                       s->q_full.bytesused += buf->bytesused;
+                       atomic_inc(&s->q_full.buffers);
                }
+               atomic_dec(&s->q_busy.buffers);
 
                ret = buf;
                break;
        }
-       mutex_unlock(&s->qlock);
 
-       /* Put lost buffers back into firmware transfer rotation */
-       while (!list_empty(&r)) {
-               buf = list_entry(r.next, struct cx18_buffer, list);
-               list_del_init(r.next);
-               cx18_enqueue(s, buf, &s->q_free);
-               cx18_vapi(cx, CX18_CPU_DE_SET_MDL, 5, s->handle,
-                      (void __iomem *)&cx->scb->cpu_mdl[buf->id] - cx->enc_mem,
-                      1, buf->id, s->buf_size);
-               CX18_INFO("Returning %s, buffer %d back to transfer rotation\n",
-                         s->name, buf->id);
-               /* and there was much rejoicing... */
-       }
+       /* Put more buffers into the transfer rotation from q_free, if we can */
+       cx18_stream_load_fw_queue_nolock(s);
+       mutex_unlock(&s->qlock);
        return ret;
 }
 
@@ -162,6 +163,7 @@ static void cx18_queue_flush(struct cx18_stream *s, struct cx18_queue *q)
 
 void cx18_flush_queues(struct cx18_stream *s)
 {
+       cx18_queue_flush(s, &s->q_busy);
        cx18_queue_flush(s, &s->q_full);
 }